Building a MythTV PVR

System components

The old desktop to be used contained an ASRock AliveNF6P-VSTA motherboard with 4GB DDR2 RAM and 2-core 2.6GHz AMD CPU, a 250GB SSD drive and Gigabyte GeForce 8400GS (nVidia) graphics card. The motherboard actually includes onboard nVidia graphics, but the only connector is VGA, and I wanted to connect to a (rather old) Sony Bravia TV via its HDMI port. Therefore the onboard graphics was disabled.

A PCIe TP-Link wireless card was fitted.

The tuners to be used were the same PCTV 292e tuners from the Windows system (connected via a D-Link hub). Note that I also had a USB August DVB T210 tuner available, but as that always had problems restarting from standby when on the Windows system (probably the driver so maybe not a Linux issue), it was not used. (Actually have now tried it with Linux using some test s/w and the libDvbV5 interface library - it is recognised OK, but doesn't seem to scan for channels correctly, no idea why).

As will become clear, in the end both the motherboard and tuners were changed - but for different reasons.

Which flavour of Linux? There is a Ubuntu release called MythBuntu, stripped down but with MythTV ready installed. This seemed an ideal launching point so that .ISO was downloaded and used as the base installation. This contains Ubuntu 14.04 LTS and MythTV 0.27.

Some general comments on Linux

If you are not used to Linux, as I wasn't, it comes as a bit of a culture shock.

In the good old days, any Unix installation required a lot of knowledge, writing of scripts and probably multiple rebuilds of the kernel to suit your hardware - it was not for the faint hearted. With Linux, and the various release flavours such as Ubuntu, it is a lot easier, and the installation process is largely automatic. However there are some points to be aware of:

1. It does not have the same level of backwards compatibility as Windows. If you have a driver that is for Kernel 3.x, there is no guarantee it will work on 3.x+1. It might, it might not.
2. There are far less drivers produced by hardware manufacturers, so most drivers needed are built into the kernel. Often it is necessary to check if there is a suitable driver for any specific bit of hardware. (There is a lot of support built into the kernel).
3. The developers tend not to be driven by commercial pressures, but by what they think is right (after all most of them are doing it for free).
4. I've heard Linux described as 'continual prototyping' and there's something in that. To me it does not seem as robust as Windows, especially in the area of updates. For instance on one occasion I performing a system update (sudo apt-get dist-upgrade) and the result was a totally unbootable system. Partition backups are advised.

Most of this is due to different (or lack of) commercial pressure, and don't forget - it's free.

An example of this will be seen later in DVB/T2 support (for HD) in the 292e. Basically MythTV appears not to support DVB/T2 correctly at the moment (0.27.6). The older tuners such as the 290e had a fudge put in the driver whereby if it tried to tune as DVB/T and that failed, it would automatically try DVB/T2. So the lack of full DVB/T2 support in MythTV support didn't matter. This was known as 'auto-switching'.

However, when it came to the 292e driver (different chip) the developer who wrote the driver decided the fudge had been there long enough, the application writers should have caught up, and did not include it. The result is the 292e on MythTV will currently not tune to DVB/T2 transports, whereas its predecessor the 290e did, and that includes the HD channels in the UK.

Who is right? One can see the developer's point. However in a commercial environment one just cannot see that happening ("we need to sell this - get that fudge in there now"). There is a happy ending though - it is however likely that the MythTV support will appear in 0.27.7, or failing that, 0.28.

On the other hand since there is less commercial pressure to fudge issues, possibly the software is cleaner.

Different pressures, so, be prepared for a fairly hands on install process.